1. Field of the Invention
This invention relates to passive barriers located on the ground and interconnected to establish a longitudinal wall that can provide security from terrorist threats by at least slowing, and preferably stopping in a short distance, a vehicle that collides with it, and by providing at least partial protection against blast wave forces, thermal energy, and flying debris from a nearby explosion event.
2. Description of the Related Art
Security zones for protecting sensitive groups of people and facilities be they private, public, diplomatic, military, or other, can be dangerous environments for people and property if threatened by acts of terrorism. Ground anchored active anti-ram vehicle barriers, bollards, and steel gates may stop a vehicle but may do little against a blast wave or blast debris. Earthen berms, sand-filled steel walls, massive concrete or plate steel walls anchored into the ground, or concrete panels laminated with steel sheeting and anchored into the ground have been used to shield against both terrorist vehicles and bombs. But none of these ground-anchored barriers are portable for ease of relocation, and all risk the possibility of interfering with underground utilities and other underground hazards.
However, both U.S. patent application Ser. No. 10/951,951 filed on Sep. 28, 2004 and titled “Massive Security Barrier” and U.S. patent application Ser. No. 11/019,043 filed on Dec. 20, 2004 and titled “Cabled Massive Security Barrier”, both incorporated herein by reference, disclose barriers that are portable for ease of relocation and do not endanger underground utilities when being deployed, installed, or removed. U.S. patent application Ser. No. 10/951,951 discloses barriers, each with at least one rectangular tie-bar of steel cast permanently within concrete or other solid material and extending longitudinally between opposite sides of the barrier, wherein adjacent barriers are coupled side-against-side by means of strong coupling devices between adjacent tie-bars, and wherein no ground penetrating anchoring means is involved. But since the tie-bars are cast within the barriers, they cannot be changed out or upgraded without removing and replacing the solid material as well. U.S. patent application Ser. No. 11/019,043 discloses barriers of solid material with tunnels extending between opposite sides, wherein adjacent barriers are coupled side-against-side with cables passing through the tunnels and anchored to sides of at least some of the barriers by anchoring devices. But since cables through tunnels between adjacent barriers are less able to resist lateral displacement between adjacent barriers compared to that when using rigidly coupled tie-bars, the use of cables limits the relative shortness of stopping distance that a wall can achieve, where stopping distance is the maximum distance any portion of a wall moves before all the kinetic energy causing an external force is absorbed.
U.S. Pat. No. 6,474,904 to Duckett et al. titled “Traffic Barrier with Liquid Filled Modules”, although not in the field of massive security barriers for protection against terrorist threats, discloses a traffic barrier design that uses a attachment members (similar in some respects to a tie-bar) through a tunnel within a cavity shaped by a plastic shell of a module body for containing water or other fluid. Duckett et al. also uses abutment members to constrain longitudinal positions of tie-bars relative to module bodies, but not relative lateral positions. However, Duckett et al. does not disclose or suggest the use of a massive block of solid material, the coupling of massive blocks side-against-side, the enablement of mutual rotation between adjacent blocks caused by a colliding vehicle or explosive blast sufficiently strong as to cause breakage of portions of the blocks that interfere with such rotation while at the same time maintaining continuity of and between coupled tie-bars, or the use of tunnels with entrance sizes closely matched to tie-bar sizes to constrain the positions of coupled ends of tie-bars relative to barrier blocks. And Duckett et al. doesn't disclose or suggest the use of side cavities to protect or constrain coupling devices and/or their retainers.
What is needed is a massive-security-barrier wall system made of massive security barriers that can be coupled into a row along the ground or other supporting surface, wherein each barrier has at least one strong tie-bar passing through it from one side of the mass of solid material of the barrier to its opposite side, wherein adjacent barriers are interconnected side-against-side by coupling the tie-bars between those adjacent barriers, wherein the tie-bar(s) of each barrier are constrained longitudinally and horizontally by the mass of solid material of that barrier to resist lateral displacement between adjacent barriers, and wherein the tie-bars can be selected at the time barriers are assembled into a barrier wall. What is needed also is the capability of exchanging or upgrading tie-bars in the field without having to replace the masses of solid material, and without the additional cost of scrapping that material. In other words, what is needed is a massive security barrier system that uses tie-bars through masses of solid material without having the tie-bars cast into the masses of solid material. The current invention provides such a system with such barriers.